A high back booster seat or child restraint designed to be used by a child during transport in vehicles or transport elements such as, for example, a car, bus, airplane and similar, which high back booster seat or child restraint is provided with a seat cushion with a rear part arranged to be located next to a back support in the vehicle or transport element. In the region of the rear part of the seat cushion (1) of the high back booster seat or child restraint on at least one side of the high back booster seat or child restraint there is arranged an illumination arrangement (7) built into the high back booster seat or child restraint, arranged to illuminate the region at the side of the high back booster seat or child restraint.